1. Field of the Invention
The present invention relates to an organic light emitting diode and a method of manufacturing the same allowing for improved stability.
2. Description of the Related Art
An organic light emitting diode (OLED) recently used in the field of displays is a self-luminous display element and has a wide viewing angle, excellent contrast, and a fast response time.
In addition, the organic light emitting diode is excellent in terms of brightness, driving voltage, and response speed characteristics, as compared to an inorganic electro-luminescence (EL) element, and may be polychromed, such that it has been prominent as a display element.
A general organic light emitting diode has a structure in which an anode is formed on an upper portion of a substrate, a light emitting layer in an organic thin film form is formed on the anode, and a cathode is formed on the light emitting layer.
In addition, a hole injection layer or a hole transport layer may be disposed between the anode and the light emitting layer, and an electron injection layer or an electron transport layer may be disposed between the light emitting layer and the cathode.
Here, the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer are organic thin film layers made of an organic compound.
Polymer OLEDs, since the organic thin film layers thereof are generally stacked through spin coating, may be relatively cheaply manufactured. However, existing lower layers may be removed during the formation of a new layer, such that it may be difficult to form a stack.
In addition, there are common problems in the formation of organic light emitting diode elements.
First, within a polymer organic thin film layer, holes have a moving speed faster than that of electrons, such that imbalance between the number of generated holes and the number of generated electrons may occur.
Second, oxygen or moisture may easily penetrate the organic layers to thereby permeate into the element, thereby deteriorating the performance and the stability of the element.
In addition, in the case of poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate), widely used as a material of the hole injection layer, protrusion due to aging may be frequently generated, such that a short-circuit between electrodes occurs.